From: John Crispin <blogic@openwrt.org>
Date: Thu, 4 Sep 2014 18:26:43 +0000 (+0200)
Subject: basic support for the cache flush bit
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=5bdbcd785b0a08e866631a6a062ea9ced1f6dce8;p=oweals%2Fmdnsd.git

basic support for the cache flush bit

Signed-off-by: John Crispin <blogic@openwrt.org>
---

diff --git a/cache.c b/cache.c
index 6240e2f..af6cbba 100644
--- a/cache.c
+++ b/cache.c
@@ -216,7 +216,7 @@ cache_host_is_known(char *record)
 }
 
 void
-cache_answer(struct interface *iface, uint8_t *base, int blen, char *name, struct dns_answer *a, uint8_t *rdata)
+cache_answer(struct interface *iface, uint8_t *base, int blen, char *name, struct dns_answer *a, uint8_t *rdata, int flush)
 {
 	struct dns_srv_data *dsd = (struct dns_srv_data *) rdata;
 	struct cache_record *r;
@@ -227,9 +227,6 @@ cache_answer(struct interface *iface, uint8_t *base, int blen, char *name, struc
 	int host_len = 0;
 	static char *rdata_buffer = (char *) mdns_buf;
 
-	if (!(a->class & CLASS_IN))
-		return;
-
 	nlen = strlen(name);
 
 	switch (a->type) {
diff --git a/cache.h b/cache.h
index b4433eb..df3593f 100644
--- a/cache.h
+++ b/cache.h
@@ -48,7 +48,7 @@ int cache_init(void);
 void cache_scan(void);
 void cache_cleanup(void);
 void cache_answer(struct interface *iface, uint8_t *base, int blen,
-		  char *name, struct dns_answer *a, uint8_t *rdata);
+		  char *name, struct dns_answer *a, uint8_t *rdata, int flush);
 int cache_host_is_known(char *record);
 char *cache_lookup_name(const char *key);
 void cache_dump_records(struct blob_buf *buf, const char *name);
diff --git a/dns.c b/dns.c
index 3f6ecbe..c5323e5 100644
--- a/dns.c
+++ b/dns.c
@@ -299,6 +299,9 @@ parse_answer(struct interface *iface, uint8_t *buffer, int len, uint8_t **b, int
 		return -1;
 	}
 
+	if ((a->class & ~CLASS_FLUSH) != CLASS_IN)
+		return -1;
+
 	rdata = *b;
 	if (a->rdlength > *rlen) {
 		fprintf(stderr, "dropping: bad question\n");
@@ -309,7 +312,7 @@ parse_answer(struct interface *iface, uint8_t *buffer, int len, uint8_t **b, int
 	*b += a->rdlength;
 
 	if (cache)
-		cache_answer(iface, buffer, len, name, a, rdata);
+		cache_answer(iface, buffer, len, name, a, rdata, a->class & CLASS_FLUSH);
 
 	return 0;
 }
diff --git a/dns.h b/dns.h
index 47727dd..791159f 100644
--- a/dns.h
+++ b/dns.h
@@ -33,6 +33,7 @@
 #define MCAST_ADDR6		"ff02::fb"
 #define MCAST_PORT		5353
 
+#define CLASS_FLUSH		0x8000
 #define CLASS_UNICAST		0x8000
 #define CLASS_IN		0x0001